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Modes
Parameters are measured for all three CCDs separately
(BLUE, REDL, REDU). They are available whenever raw arclamp (type LAMP,WAVE)
frames are measured.
Since Period 68 (Oct.
01, 2001) a set of daily arclamp exposures is taken which serves as instrument
health check, in the two settings BLUE 437 1x1 and RED 580 1x1 and with
slit widths 0.4 and 0.3 arcsec, resp. These are used to monitor the resolving
power of UVES.
QC1 parameters:
resolving power, dispersion, line intensity
The most important QC1 parameters measured are resolving power R
and standard deviation of the dispersion solution, sigma.
Others are e.g. minimum and maximum wavelength and number of lines selected.
Most of the collected QC1 parameters are trended for the two
daily health check modes here:
BLUE
and
RED
Resolving power R = lambda/delta lambda is
evaluated as median over a Gauss fit to all selected lines. R is
compared to reference values as function of slit width. The reference
values are lab data as taken from the User's Manual.
The quality of the dispersion solution is measured by the standard deviation
of the difference between the found and fitted position, again evaluated
for all selected lines. Typically 300 - 1000 lines are selected per CCD.
| parameter |
procedure |
applied |
typical
values
|
plots |
| |
|
|
setting
|
value*
|
|
| effective resolving power
R |
Gauss fit to selected lines,
median of FWHM |
line table |
BLUE, 0.5": |
70 000 |
resolution
1,2,3: trending of R vs. time for
BLUE, REDL and REDU chips for the
DHC modes
4,5,6: all R values from the selected period vs.
slit width; plus signs and broken curve are
nominal values, for BLUE, REDL and REDU chips
|
| REDU, 0.5": |
80 000 |
| REDL, 0.5": |
80 000 |
| sigma of dispersion
solution |
least-square fit of X position of selected lines,
standard deviation of residuals |
line table |
BLUE_1x1/
BLUE_2x2: |
1x1: 2-3 mA**
2x2: 5-7 mA** |
dispersion
trending of sigma vs.
time: For Blue, plot 6 of
BLUE
and for RED, plots 6 & 12 of
RED
|
REDU_1x1/
REDU_2x2: |
1x1: 4-6 mA**
2x2: 8-15 mA** |
REDL_1x1
REDL_2x2: |
1x1: 2-4 mA**
2x2: 5-9 mA** |
|
* in Oct-Dec 2000
** depending on wavelength and slit width
|